Battery charge management using a scheduling application

ABSTRACT

According to some embodiments, battery charge management using a scheduling application is disclosed. A first parameter may be received from a scheduling application running on a mobile computing device having a battery pack. Based on at least the first parameter and battery pack data, a required charge percentage for the battery pack may be determined and the remaining capacity of the battery pack may be determined. If the remaining capacity of the battery pack is less than the required charge percentage, a charge termination voltage may be determined and the battery pack may be charged to the charge termination voltage.

BACKGROUND

Typically, the battery pack of a mobile device such as a notebookcomputer will be charged to 100% capacity when an AC (alternatingcurrent) adapter is connected to the mobile device. The battery pack isdischarged when the AC adapter is disconnected from the mobile deviceand the mobile device is operating on battery power. Battery capacitygradually decreases as a mobile device is used. For example, at 500battery charge cycles, the battery capacity may decrease toapproximately 60% of its initial capacity. Furthermore, the batterycapacity may diminish if the battery is never discharged because thebattery can degrade at high voltages.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of embodiments of the present invention can beobtained from the following detailed description in conjunction with thefollowing drawings, in which:

FIG. 1 is a block diagram of a system according to some embodiments.

FIG. 2 is a diagram illustrating how a charge management moduleinteracts with components within a mobile computing device according tosome embodiments.

FIG. 3 is a flow diagram according to some embodiments.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth.However, it is understood that embodiments of the invention may bepracticed without these specific details. In other instances, well-knowncircuits, structures and techniques have not been shown in detail inorder not to obscure an understanding of this description.

References to “one embodiment”, “an embodiment”, “example embodiment”,“various embodiments”, etc., indicate that the embodiment(s) of theinvention so described may include particular features, structures, orcharacteristics, but not every embodiment necessarily includes theparticular features, structures, or characteristics. Further, someembodiments may have some, all, or none of the features described forother embodiments.

In the following description and claims, the terms “coupled” and“connected,” along with their derivatives, may be used. It should beunderstood that these terms are not intended as synonyms for each other.Rather, in particular embodiments, “connected” is used to indicate thattwo or more elements are in direct physical or electrical contact witheach other. “Coupled” is used to indicate that two or more elementsco-operate or interact with each other, but they may or may not be indirect physical or electrical contact.

FIG. 1 is a block diagram of a system according to some embodiments. Thesystem may include platform hardware 120, which may include one or moreof a processor 124, a chipset 122, and/or other components that are notillustrated for clarity, such as volatile or non-volatile memory, anetwork interface, and input/output devices.

The platform hardware 120, including one or more of chipset 122 and/orprocessor 124, may be coupled to a charge management module 110. Thecharge management module 110 may be further coupled to an AC/DC(alternating current/direct current) adapter 102, a power monitor 104, apower switch 112, and a battery pack 114. The power monitor 104 maysense current from the AC/DC adapter 102 by measuring the voltage acrossresistor 103. The power switch 112 may be used to switch the flow ofcurrent from one battery pack 114 to another during charge and dischargeif multiple battery packs 114 are being used. The system managementcontroller (SMC) 108 may be coupled to the battery pack 114 to receivebattery pack information. SMC 108 may also be coupled to a selector 106,and may indicate to the selector 106 which battery pack 114 should becharged and/or used if multiple battery packs 114 are attached.

The charge management module 110 may include hardware and/or software toswitch between an AC/DC adapter 102 providing power from an AC powersource 101 and battery power from a battery pack 114. Battery pack 114may include a battery management unit 116 and one or more battery cells118.

In some embodiments, the charge management module 110 may monitorportions of the system to determine when to switch to AC power to chargethe battery pack 114 and/or when to switch to battery power to draw downthe charge of the battery pack 114. The charge management module 110 maymonitor one or more characteristics of the battery pack 114 via thebattery management unit (BMU) 116, including but not limited to batterypack capacity, pack voltage, voltage for each battery cell 118, cyclecount, temperature, and current through the BMU. The charge managementmodule 110 may also monitor a user's schedule or calendar via ascheduling application running on processor 124.

Based on the user's schedule and the battery characteristics, the chargemanagement module 110 may determine the percentage of battery chargethat is required for the next time period when the user will not have ACpower available from an AC power source (e.g., when the user isscheduled to be in a meeting). The charge management module 110 may thendetermine the charge termination voltage required to meet the requiredbattery charge percentage. The charge management module 110 may alsoestimate how long it will take the battery to charge to the desiredcharge termination voltage. If the length of time to charge the batteryto the desired voltage is greater than the time the user will have ACpower available, the charge management module 110 may notify the user,for example via the scheduling application or another notificationmechanism. If the length of time to charge the battery is less than thetime the user will have AC power available, the charge management module110 may switch to AC power if battery power is presently being used, andmay charge the battery to the desired charge termination voltage. If thebattery voltage is greater than the desired charge termination voltage,the charge management module 110 may switch from AC power to batterypower to discharge the battery to the appropriate voltage.

FIG. 2 is a diagram illustrating how a charge management moduleinteracts with components within a mobile computing system according tosome embodiments. The charge management module 208 may receiveinformation from both system hardware and system software.

The battery management unit 206 may monitor the battery cells 204 withina battery of a mobile computing device. The battery management unit 206may provide the charge management module 208 with battery pack data. Thebattery pack data may include one or more of battery pack capacity,battery voltage, cell voltage for each cell, cycle count, temperature,and current.

The battery management driver 210 may monitor a schedule application 214running on an operating system 212. The battery management driver 210may provide the charge management module 208 with information about auser's schedule. For example, if a user's calendar in scheduleapplication 214 includes a meeting, an out of office notice, or avacation notice, this may indicate that the user will need to use themobile computing system in a battery operated state. In someembodiments, adjacent calendar entries indicating that battery power maybe necessary may be treated as a single calendar entry having a durationthat is equal to the sum of the durations of each adjacent calendarentry for the purposes of battery management.

Based on the user's calendar in schedule application 214, the batterymanagement driver 210 may provide information to the charge managementmodule 208 about the time and duration of the next calendar period thatindicates battery operation may be necessary. Based on the user'scalendar in schedule application 214, the battery management driver 210may also provide information to the charge management module 208 aboutthe length of time AC power will be available before battery operationmay be necessary.

In some embodiments, the charge management module 208 may charge ordischarge the battery cells 204 based on information received from theschedule application 214 via the operating system 212 and batterymanagement driver 210 and also based on information received from thebattery management unit 206.

In some embodiments, all or some of the functions of the chargemanagement module 208 may be performed by the battery management driver210, and the charge management module may thus be wholly or partiallyintegrated into the battery management driver 210.

FIG. 3 is a flow diagram illustrating a method according to someembodiments. The method may begin at block 302, with receiving at leastone parameter from a scheduling application running on an operatingsystem on a mobile computing device. The parameter(s) received from thescheduling application may include, for example, a length of time that amobile computing device will be operating on battery power and/or alength of time that the mobile computing device will be connected to ACpower before operating on battery power.

The method may continue at block 304, with calculating a required chargepercentage for a battery based on the at least one parameter and batterypack data. In some embodiments, the battery pack data may be obtainedfrom a battery management unit. At block 306, the actual remainingbattery capacity may be determined.

If the remaining battery capacity is less than the required chargepercentage, as shown in block 308, this is an indication that thebattery must be charged. If the remaining battery capacity is greaterthan the required charge percentage, this is an indication that thebattery must be discharged to reach the appropriate voltage. In thiscase, as shown in block 316, AC power may be disconnected from themobile computing device such that the device operates on battery power.In this manner, the battery may be discharged to the charge terminationvoltage.

When the remaining battery capacity is less than the required chargepercentage, a charge termination voltage may be determined, as shown inblock 310. Based upon at least the remaining battery capacity and thecharge termination voltage, a time to charge completion may beestimated, as shown in block 312. If the time to charge completion isgreater than the length of time the mobile computing device will beconnected to AC power before operating on battery power, the user of themobile computing device may be notified that there is insufficient timeto charge the battery, as shown in block 312. In some embodiments, theuser may be notified of insufficient charge time via the schedulingapplication or may be notified in another manner. If the charge time isinsufficient, the battery may be charged continuously until AC power isremoved at the time indicated by the scheduling application.

After the charge termination voltage is determined, the mobile computingdevice may be switched from battery power to AC power, if AC power isnot already being used, and the battery may be charged to the chargetermination voltage, as indicated by block 314.

In some embodiments, the method illustrated in FIG. 3 may be performedby one or more of a charge management module, a battery managementdriver, or other hardware and/or software within a mobile computingdevice.

Various embodiments described herein may be implemented in one or anycombination of hardware, firmware, and software. Some embodiments mayalso be implemented as instructions contained in or on amachine-readable medium, which may be read and executed by one or moreprocessors to enable performance of the operations described herein. Amachine-readable medium may include any mechanism for storing,transmitting, and/or receiving information in a form readable by amachine (e.g., a computer). For example, a machine-readable medium mayinclude a storage medium, such as but not limited to read only memory(ROM); random access memory (RAM); magnetic disk storage media; opticalstorage media; a flash memory device, etc. A machine-readable medium mayalso include a propagated signal which has been modulated to encode theinstructions, such as but not limited to electromagnetic, optical, oracoustical carrier wave signals.

Thus, battery charge management using a scheduling application isdisclosed in various embodiments. In the above description, numerousspecific details are set forth. However, it is understood thatembodiments may be practiced without these specific details. In otherinstances, well-known circuits, structures, and techniques have not beenshown in detail in order not to obscure the understanding of thisdescription. Embodiments have been described with reference to specificexemplary embodiments thereof. It will, however, be evident to personshaving the benefit of this disclosure that various modifications andchanges may be made to these embodiments without departing from thebroader spirit and scope of the embodiments described herein. Thespecification and drawings are, accordingly, to be regarded in anillustrative rather than a restrictive sense.

1. A method comprising: receiving a first parameter from a schedulingapplication running on a mobile computing device having a battery pack;calculating a required charge percentage for the battery pack based onat least the first parameter and battery pack data; determining aremaining capacity of the battery pack; and if the remaining capacity ofthe battery pack is less than the required charge percentage,determining a charge termination voltage and charging the battery packto the charge termination voltage.
 2. The method of claim 1, furthercomprising receiving a second parameter from the scheduling application.3. The method of claim 2, wherein the first parameter is a length oftime the mobile computing device will be operating on battery power andthe second parameter is a length of time the mobile computing devicewill be connected to an AC power source before operating on batterypower.
 4. The method of claim 3, further comprising if the remainingcapacity of the battery pack is less than the required chargepercentage, estimating a time to charge completion.
 5. The method ofclaim 4, further comprising notifying a user of the mobile computingdevice if the time to charge completion is greater than the length oftime the mobile computing device will be connected to the AC powersource before operating on battery power.
 6. The method of claim 5,wherein notifying the user comprises notifying the user via thescheduling application.
 7. The method of claim 1, wherein the batterypack data includes temperature, cycle count, and current.
 8. The methodof claim 1, further comprising if the remaining capacity of the batterypack is greater than the required charge percentage, disconnecting ACpower and using battery power to discharge the battery pack to thecharge termination voltage.
 9. A system comprising: a processor to run aschedule application; an AC/DC adapter to provide power from an AC powersource; a battery pack; a charge management module coupled to theprocessor, the AC/DC adapter, and the battery pack, the chargemanagement module to monitor battery pack data and to monitor a user'sschedule via the schedule application; wherein the charge managementmodule is to determine a length of time a user will be connected to theAC power source via the AC/DC adapter before the battery pack is used,to determine a length of time the battery pack will be used based uponthe schedule application, and to determine a charge termination voltage.10. The system of claim 9, wherein the charge management module isfurther to determine a time to charge completion.
 11. The system ofclaim 10, wherein the charge management module is to permit the AC/DCadapter to charge the battery pack if the time to charge completion isless than the length of time the user will be connected to the AC powersource via the AC/DC adapter before the battery pack is used.
 12. Thesystem of claim 11, wherein the charge management module is further toswitch from the AC power source to battery pack power when the batterypack reaches the charge termination voltage.
 13. The system of claim 9,wherein the charge management module is to switch from the AC powersource to battery pack power to discharge the battery pack to the chargetermination voltage if a remaining battery capacity is greater than thecharge termination voltage.
 14. The system of claim 9, wherein thebattery pack data includes temperature, cycle count, and current.